It's probably Final Fantasy XIV, since I've bought all the expansions. I really don't spend very much on DLC. When I do buy it, I tend to wait until a season pass will go on sale for quite cheap.
I'm not sure which is on top, but it's either Rock Band or Pinball Arcade. The former because I bought at least two albums and assorted songs back in the day, and the latter because of all the Bally and Williams tables being taken down due to licensing. I think I bought everything just before the takedown deadline.
Probably Team Fortress 2 since during a couple halloween events I didn't have time to play so I just bought everything. Overwatch may be close with all the times I dropped money on event boxes on a whim or again was too busy with work to thoroughly play an event.
Dissidia 012. I was buying every single costume, music track, etc week after week. In the end the only thing that stopped me was when PSN got hacked and Sony took the entire service down, interrupting the regular distribution of DLC from S-E for an extended period of time and I finally stopped playing the game.
I think it's Smash Ultimate unless all character DLC + 64 stages in Smash 4 cost more than the two fighter passes (got Mewtwo for free and did at least one bundle swap with a 3DS player)
Oh easy, Sims 4. You'll spend hundreds of dollars to get the whole damn thing.
(But it's worth it. You basically get.... 100000 times more content ? It's crazy)
Also the game I've spent most TIME playing its dlc. Totally worth it for me.
No an MMO or online gamer by and large, have played my fair share of BR games but never really bought into cosmetics. Played Dota for 1k+ hours though, have definitely put money into plenty of compendiums and the like, but I'd say I made all that money back by selling all the cosmetics down the line.
The Civilization games are the first thing that came to mind for "DLC" purchases. Goddam devs releasing the 'lite' version of their games at launch and then you've gotta buy the rest of the features as they complete them. I swear the only reason they get away with their shenanigans is because their games are so damn good.
If we also include MTX, it's League of Legends and it's not even close. It is an obscene sum by any definition thereof. And I don't even play it anymore (thankfully). If we're just talking about extra content for games, probably Destiny 2. By the time I get around to DLC, it's usually on sale.
Hearthstone, couple of hundred on packs, expansions and adventures over 6ish years.
I'm now basically F2P because the economy and cost of trying to stay competitive is so much ludicrously higher than it used to be. Also Blizzard's actions and ethics as of late are not something I feel comfortable paying in to.
Those extra songs were certainly worthwhile though!
Think I also paid for two or maybe three (am a little bit embarrassed to admit this) gold bags on the very first Infinity Blade (by the developers of the rather superb 'Shadow Complex'), as I was really struggling to go toe-to-toe with the God King with my fairly feeble weapon that was upgraded much quicker, thanks to buying those 💰.
Hearthstone and it's not even particularly close. Easily hundreds, if not thousands, of dollars through all of the new content, adventure modes, and packs.